Patient-Specific Implant for Primary Orbital Reconstruction: A Case Report

ABSTRACT @#The main aim of orbital fracture reconstruction is to restore the functional and aesthetic components of the eye. However, it is known that surgery for complex three-dimensional anatomy of the orbit is always a challenge. With recent advancements in technology, surgical predictability and outcomes have greatly improved. Several methods for orbital reconstruction surgery have been documented such as virtual surgical planning, intraoperative navigation, intraoperative imaging, and the use of patient-specific implant (PSI). PSI made of titanium can be designed by using a computer-aided design process and manufacturing (CAD-CAM) of CT-scan routinely used during diagnostic imaging. With precise analyses in shape and size followed by personalised implant design, the surgical precision can be alleviated further and at the same time, the surgical duration could be reduced with anticipation of better surgical outcomes. However, meticulous planning needs to be done preoperatively, with the timing of the surgery being an important factor. In the present case, pure orbital blowout fracture primarily treated with a personalised-implant solution derived from 3D-printing technology is described. Both pre-surgical and surgical workflow of this computer-assisted surgical method is elaborated. PSI for primary orbital reconstruction can be regarded as a viable alternative surgical solution including its working timeframe and adherence to the surgical protocol or algorithm.

Late correction of orbital deformities using customized 3D implant / Corrección tardía de deformidades de órbita usando implantes personalizados 3D

SUMMARY: Late orbital reconstruction is a complex and challenge for surgeons. The aim of this article is to present complex orbital reconstruction using patient specific implant (PSI) strategy and polyetheretherketone (PEEK). A literature review and a cases series of sequelae after complex orbital trauma are presented; cases with great middle third deformities showing defect in the maxilla, nasal area, body of the zygoma and zygomatic arch were included; in both cases the sequelae was for more than 10 years. Virtual planning and PEEK implants were manufacture using a puzzle (two or three parts) by 3D print or injection. Patients were treated and their surgeries carried out without complications, using a minimal surgical approach. No infections were observed, and after 12 months follow-up they were stable showing normal function. PSI based-PEEK for orbital reconstruction are safe, efficient, effective and to obtain orbital morphology with low complications.

RESUMEN: La reconstrucción tardía de la órbita es un desafío complejo para cirujanos. El objetivo de este artículo fue presentar la reconstrucción orbitaria compleja utilizando implante paciente específico (PSI) y polietereterketona (PEEK). Son presentados una revisión de literatura y una serie de casos con secuelas posteriores a un trauma orbitario complejo; además, son presentados casos con gran deformidad del tercio medio del rostro mostrando defectos en maxila, área nasal, cuerpo del hueso cigomático y arco cigomático; ambos casos de secuela fueron por más de 10 años. Planificación virtual e implantes en PEEK fueron creados usando una estrategia de puzzle (dos o tres partes) por inyección o impresión 3D. Los pacientes fueron tratados y sus cirugías realizadas sin complicaciones usando accesos quirúrgicos reducidos. No se observaron infecciones y después de 12 meses de seguimiento permanecieron estables mostrando función normal. Los PSI para reconstrucción orbitaria son seguros, eficientes, efectivos y recuperan morfología de órbita con bajas complicaciones.

A retrospective study to compare the treatment outcomes with and without surgical navigation for fracture of the orbital wall / 中华创伤杂志(英文版)

PURPOSE@#To evaluate the outcomes with and without aid of a computer-assisted surgical navigation system (CASNS) for treatment of unilateral orbital wall fracture (OWF).@*METHODS@#Patients who came to our hospital for repairing unilateral traumatic OWF from 2014 to 2017 were included in this study. The patients were divided into the navigation group who accepted orbital wall reconstruction aided by CASNS and the conventional group. We evaluated the surgical precision in the navigation group by analyzing the difference between actual postoperative computed tomography data and preoperative virtual surgical plan through color order ratios. We also compared the duration of surgery, enophthalmos correction, restoration of orbital volumes, and improvement of clinical symptoms in both groups systemically. Quantitative data were presented as mean ± SD. Significance was determined by the two-sample t-test using SPSS Version 19.0 A p < 0.05 was considered statistically significant.@*RESULTS@#Seventy patients with unilateral OWF were included in the study cohort. The mean difference between preoperative virtual planning and actual reconstruction outcome was (0.869 ± 0.472) mm, which means the reconstruction result could match the navigation planning accurately. The mean duration of surgery in the navigation group was shorter than it is in the control group, but not significantly. Discrepancies between the reconstructed and unaffected orbital-cavity volume and eyeball projection in the navigation group were significantly less than that in the conventional group. One patient had remnant diplopia and two patients had enophthalmos after surgery in the navigation group; two patients had postoperative diplopia and four patients had postoperative enophthalmos in the conventional group.@*CONCLUSION@#Compare with the conventional treatment for OWF, the use of CASNS can provide a significantly better surgical precision, greater improvements in orbital-cavity volume and eyeball projection, and better clinical results, without increasing the duration of surgery.

Computer-assisted navigation in orbitofacial surgery

The purpose of this systematic review is to investigate the most common indications, treatment, and outcomes of computer-assisted surgery (CAS) in ophthalmological practice. CAS has evolved over the years from a neurosurgical tool to maxillofacial as well as an instrument to orbitofacial surgeries. A detailed and organized scrutiny in relevant electronic databases, journals, and bibliographies of the cited articles was carried out. Clinical studies with a minimum of two study cases were included. Navigation surgery, posttraumatic orbital reconstruction, computer-assisted orbital surgery, image-guided orbital decompression, and optic canal decompression (OCD) were the areas of interest. The search generated 42 articles describing the use of navigation in facial surgery: 22 on orbital reconstructions, 5 related to lacrimal sac surgery, 4 on orbital decompression, 2 articles each on intraorbital foreign body and intraorbital tumors, 2 on faciomaxillary surgeries, 3 on cranial surgery, and 2 articles on navigation-guided OCD in traumatic optic neuropathy. In general, CAS is reported to be a useful tool for surgical planning, execution, evaluation, and research. The largest numbers of studies and patients were related to trauma. Treatment of complex orbital fractures was greatly improved by the use of CAS compared with empirically treated control groups. CAS seems to add a favourable potential to the surgical armamentarium. Planning details of the surgical approach in a three-dimensional virtual environment and execution with real-time guidance can help in considerable enhancement of precision. Financial investments and steep learning curve are the main hindrances to its popularity.

Progress in reconstruction of orbital wall after fracture / 国际眼科杂志(Guoji Yanke Zazhi)

·At present, the orbital wall fracture is a very common facial trauma. The orbital contents are often incarcerated in the fracture cracks resulting in changes in the orbital eye position, then can bring a lifetime of diplopia and enophthalmos,which greatly affects the visual acuity and facial appearance. The purpose of repairing of orbital fracture is reconstructing orbital wall, repairing defect to correct eye position, avoiding enophthalmos and recovering visual function. The review will provide a comprehensive overview of orbital fracture reconstruction.

Transnasal Reduction of Blow Out Fracture with Transconjunctival Approach

PURPOSE: Many surgical approaches for reconstruction of blow out fracture have been introduced, which include subciliary incision, transconjunctival incision and transcaruncular incision. Recently endoscopic approach has been attempted. This study was intended to show the effectiveness of the approach through transconjunctival incision combined with transnasal reduction in reconstructing blow out fracture to its original position. METHODS: Medical recoreds of 43 patients from March 2008 to March 2009 who underwent surgery for orbital fracture were reviewed, retrospectively. All fractures were operated through transconjuctival incision approach combined with transnasal reduction. The average follow-up period was 10.1 months. To evaluate the surgical outcomes of orbital fracture, we performed CT of the facial bone before and after the surgery. In addition, preoperative and postoperative data of enophthalmos, diplopia and the limitation of extraocular motion was assessed with physical examination. RESULTS: Post-operative CT scan of 43 patients assured that the bone fragments of the orbital fractures were restored to their original positions. Although a few patients developed postoperative transient diplopia or impairment of ocular movement, most of the patients recovered during the follow-up period without complication. CONCLUSION: From this study, we were able to demonstrate the effectiveness of the transnsasal reduction technique combined with the approach through transconjunctival incision. This technique can be considered as very useful means of repairing orbital fracture. It is not only easy to perform but also it can minimize the damage to the orbital bone. Furthermore, it can restore the fracture to its original position as much as possible.

Tissue repair after orbital reconstruction using polypropylene mesh implants: A histological study in dogs / Reparo tecidual após reconstrução de órbita com implante de malha de polipropileno: um estudo histológico em cães

Purpose: This experimental study aimed to assess the histological outcomes of orbit reconstruction with a polypropylene mesh implant in an animal model using dogs. Methods: The right and left orbits of 12 dogs were fractured in order to simulate orbital fractures similar to those occurring in humans as a result of trauma. The orbits were reconstructed with a polypropylene mesh positioned approximately 10 mm beyond the bone defect borders. The 24 orbits were divided into four groups of six: one group was given one polypropylene mesh layer; another group received two layers; a third group was given three polypropylene mesh layers; and the fourth group did not receive any implant (control group). The dogs were divided into clusters of four animals and were euthanized 15, 30, or 60 days after the surgery. The orbit medial wall was removed, and samples were subjected to histological polypropylene mesh analysis by optical microscopy. Data were analyzed using a non-parametric test with a 5% level of significance. Results: It was found that the polypropylene mesh caused a mild to moderate tissular reaction. Conclusion: The implant was well tolerated even with two or three overlapping layers.

Objetivo: Trata-se de estudo experimental em que se reconstruíram os continentes orbitais de 12 cães com implante de tela de polipropileno. Metodologia: Os continentes orbitais foram fraturados simulando as fraturas orbitais que ocorrem em humanos devido ao trauma e reconstruídas com tela de polipropileno cortadas com extensão de cerca de 10mm além da margem do defeito ósseo. Utilizaram-se uma, duas ou três camadas de tela de polipropileno nas órbitas teste e algumas órbitas, somente fraturadas, serviram como controle. Os cães foram sacrificados nos tempos de 15, 30 e 60 dias de pós-operatório; os tecidos das órbitas teste e controle foram removidos e preparados para análise histológica em microscopia óptica. Os resultados obtidos pela análise histológica foram submetidos a análise estatística não paramétrica com 5% de significância. Resultados: A tela de polipropileno causou reação tecidual de leve a moderada nos tecidos. Conclusão: O implante foi bem tolerado, mesmo quando a tela foi superposta em duas ou três camadas.

An Analysis of Orbital Reconstruction with Bioresorbable Plate Through Orbital Volume Assessment

PURPOSE: To evaluate the early effect of orbital reconstruction with MacroPore(R) by assessment of orbital volume through orbital computed tomography (CT) in cases of orbital wall fracture METHODS: We performed orbital reconstruction with MacroPore(R) in patients with orbital wall fracture smaller than 3 cmx2 cm. Orbital CT was done preoperatively and 6 months postoperatively. We then evaluated the results by measuring the orbital volume through Rapidia 2.8 program. RESULTS: The study comprised 14 patients. The site of fracture was the medial wall in one patient, inferior in seven, and both medial and inferior in six patients. The site of insertion of MacroPore(R) was the medial wall in one patient, inferior in 12, and both medial and inferior walls in one. The mean volume of the affected orbit before operation was 20.23+/-2.78 cm3, that of the unaffected orbit was 18.27+/-2.24 cm3 (p-value=0.000), and the mean volume of the affected orbit after operation was 19.06+/-2.57 cm3, that of the unaffected orbit was 18.06+/-2.24 cm3 (p-value=0.000). The mean enophthalmos before operation was 1.00+/-0.62mm, and after operation was 0.64+/-0.46 mm. The mean difference of orbital volume between the affected and the unaffected orbits before operation was 1.96+/-0.33 cm3, and 1.00+/-0.87 cm3 after operation (p-value=0.000). The mean volume of the affected orbit before operation was 20.23+/-2.77 cm3, and 19.06+/-2.57 cm3 after operation (p-value=0.000). Each cubic centimeter decrement in volume caused a 0.67+/-0.68 mm mean decrease of enophthalmos. CONCLUSIONS: We concluded that MacroPore(R) was safe orbital implant and effective in decreasing the orbital volume at early orbital reconstruction in cases of orbital wall fracture smaller than 3 cmx2 cm through a comparison of orbital volume before and after operation.